Image of the JetBlue Sign Rendering (JetBlue Airways)

LONG ISLAND CITY — The three giant signs that mark the Queens waterfront have become as much a part of the city’s scenery as Manhattan’s high-rises or East River bridges.

Seen by tens of thousands of drivers every day, the signs for Pepsi, IDCNY and Silvercup Studios are an advertiser’s dream, and now JetBlue wants to join them.

The airline moved its headquarters from Forest Hills to a historic Brewster building in Queens Plaza earlier this month, and is seeking a zoning change to allow it to erect an enormous L.E.D. “JetBlue” sign of the rooftop of its building. The sign would be blue during the day and bright white at night.

The zoning variance, which JetBlue applied for in February 2011, would open the door for other new signs to be placed on the top of non-residential buildings in a 14-block